Motion-activated cameras capture animals being wild, weird

This 2011 photo from a U.S. Fish and Wildlife Service motion-activated camera shows an elephant seal in the Channel Islands National Park off the coast of Southern California. Motion-detecting wildlife cameras devices are getting smaller, cheaper and more reliable, and scientists across the United State are using them to document elusive creatures like never before. (U.S. Fish and Wildlife Service via AP)

This 2017 photo from a U.S. Fish and Wildlife Service motion-activated camera shows an osprey poses at the Back Bay National Wildlife Refuge in Virginia. Motion-detecting wildlife cameras are yielding serious science as well as amusing photos. From ocelots in the desert to snow-loving lynx high in the Northern Rockies, remote cameras are exposing elusive creatures like never before. (U.S. Fish and Wildlife Service via AP)

This 2017 photo from a U.S. Fish and Wildlife Service motion-activated camera shows a black bear at the Florida Panther National Wildlife Refuge. Motion-detecting wildlife cameras are yielding serious science as well as amusing photos. From ocelots in the desert to snow-loving lynx high in the Northern Rockies, remote cameras are exposing elusive creatures like never before. (U.S. Fish and Wildlife Service via AP)

This 2017 photo from a U.S. Fish and Wildlife Service motion-activated camera shows a moose at the Yukon Flats National Wildlife Refuge in Alaska. Motion-detecting wildlife cameras are yielding serious science as well as amusing photos. From ocelots in the desert to snow-loving lynx high in the Northern Rockies, remote cameras are exposing elusive creatures like never before. (U.S. Fish and Wildlife Service via AP)

This 2013 photo from a U.S. Fish and Wildlife Service motion-activated camera shows a bighorn sheep at the Kofa National Wildlife Refuge in Arizona. Motion-detecting wildlife cameras are yielding serious science as well as amusing photos. (U.S. Fish and Wildlife Service via AP)

In this 2012 photo from a U.S. Fish and Wildlife Service motion-activated camera, a golden eagle confronts a desert bighorn sheep at Desert National Wildlife Refuge in Nevada. Motion-detecting wildlife cameras are getting smaller, cheaper and more reliable, and scientists across the United State are using them to document elusive creatures like never before. (U.S. Fish and Wildlife Service via AP)

In this 2015 photo from a Wyoming Cooperative Fish and Wildlife Research Unit motion-activated camera, an adult bull elk walk in the Teton Wilderness Area of Wyoming. Motion-detecting wildlife cameras are yielding serious science as well as amusing photos. (Wyoming Cooperative Fish and Wildlife Research Unit via AP)

In this 2017 photo from a U.S. Fish and Wildlife Service motion-activated camera, a vulture comes in for a landing at the Sevilleta National Wildlife Refuge in New Mexico. Motion-detecting wildlife cameras are yielding serious science as well as amusing photos. From ocelots in the desert to snow-loving lynx high in the Northern Rockies, remote cameras are exposing elusive creatures like never before. (U.S. Fish and Wildlife Service via AP)

This 2017 photo from a U.S. Fish and Wildlife Service motion-activated camera shows a Florida panther at Florida Panther National Wildlife Refuge. Motion-detecting wildlife cameras are yielding serious science as well as amusing photos. (U.S. Fish and Wildlife Service via AP)

In this 2016 photo from a Wyoming Cooperative Fish and Wildlife Research Unit motion-activated camera, an adult cow moose walks in a snowstorm in the Gros Ventre area of Wyoming. Motion-detecting wildlife cameras are yielding serious science as well as amusing photos. (Wyoming Cooperative Fish and Wildlife Research Unit via AP)

This 2011 photo from a U.S. Fish and Wildlife Service motion-activated camera shows an elephant seal in the Channel Islands National Park off the coast of Southern California. Motion-detecting wildlife cameras devices are getting smaller, cheaper and more reliable, and scientists across the United State are using them to document elusive creatures like never before. (U.S. Fish and Wildlife Service via AP)

This 2017 photo from a U.S. Fish and Wildlife Service motion-activated camera shows an osprey poses at the Back Bay National Wildlife Refuge in Virginia. Motion-detecting wildlife cameras are yielding serious science as well as amusing photos. From ocelots in the desert to snow-loving lynx high in the Northern Rockies, remote cameras are exposing elusive creatures like never before. (U.S. Fish and Wildlife Service via AP)

This 2017 photo from a U.S. Fish and Wildlife Service motion-activated camera shows a black bear at the Florida Panther National Wildlife Refuge. Motion-detecting wildlife cameras are yielding serious science as well as amusing photos. From ocelots in the desert to snow-loving lynx high in the Northern Rockies, remote cameras are exposing elusive creatures like never before. (U.S. Fish and Wildlife Service via AP)

This 2017 photo from a U.S. Fish and Wildlife Service motion-activated camera shows a moose at the Yukon Flats National Wildlife Refuge in Alaska. Motion-detecting wildlife cameras are yielding serious science as well as amusing photos. From ocelots in the desert to snow-loving lynx high in the Northern Rockies, remote cameras are exposing elusive creatures like never before. (U.S. Fish and Wildlife Service via AP)

This 2013 photo from a U.S. Fish and Wildlife Service motion-activated camera shows a bighorn sheep at the Kofa National Wildlife Refuge in Arizona. Motion-detecting wildlife cameras are yielding serious science as well as amusing photos. (U.S. Fish and Wildlife Service via AP)

In this 2012 photo from a U.S. Fish and Wildlife Service motion-activated camera, a golden eagle confronts a desert bighorn sheep at Desert National Wildlife Refuge in Nevada. Motion-detecting wildlife cameras are getting smaller, cheaper and more reliable, and scientists across the United State are using them to document elusive creatures like never before. (U.S. Fish and Wildlife Service via AP)

In this 2015 photo from a Wyoming Cooperative Fish and Wildlife Research Unit motion-activated camera, an adult bull elk walk in the Teton Wilderness Area of Wyoming. Motion-detecting wildlife cameras are yielding serious science as well as amusing photos. (Wyoming Cooperative Fish and Wildlife Research Unit via AP)

In this 2017 photo from a U.S. Fish and Wildlife Service motion-activated camera, a vulture comes in for a landing at the Sevilleta National Wildlife Refuge in New Mexico. Motion-detecting wildlife cameras are yielding serious science as well as amusing photos. From ocelots in the desert to snow-loving lynx high in the Northern Rockies, remote cameras are exposing elusive creatures like never before. (U.S. Fish and Wildlife Service via AP)

This 2017 photo from a U.S. Fish and Wildlife Service motion-activated camera shows a Florida panther at Florida Panther National Wildlife Refuge. Motion-detecting wildlife cameras are yielding serious science as well as amusing photos. (U.S. Fish and Wildlife Service via AP)

In this 2016 photo from a Wyoming Cooperative Fish and Wildlife Research Unit motion-activated camera, an adult cow moose walks in a snowstorm in the Gros Ventre area of Wyoming. Motion-detecting wildlife cameras are yielding serious science as well as amusing photos. (Wyoming Cooperative Fish and Wildlife Research Unit via AP)

Some charismatic critters caught by motion-detecting wildlife cameras seem to know how to strike a pose. But it’s not just show business. As these devices get ever smaller, cheaper and more reliable, scientists across the U.S. are using them to document elusive creatures like never before.

“There’s no doubt — it is an incredible tool to acquire data on wildlife,” said Grant Harris, a U.S. Fish and Wildlife Service wildlife biologist based in Albuquerque, New Mexico.

Remote cameras have photographed everything from small desert cats called ocelots to snow-loving lynx high in the Northern Rockies.

Harris cited images of javelinas, pig-like desert mammals, and coatimundi, members of the raccoon family, captured at higher latitudes in recent years. That could mean global warming is expanding their range northward, he said.

Scientists deploying remote cameras include researchers with the Wyoming Migration Initiative, who use global positioning to map the movements of elk, mule deer and antelope in and around Yellowstone National Park. They only have so many collars to track animals, meaning there’s a limit to the GPS data they can gather, said Matthew Kauffman, a University of Wyoming associate professor and initiative director.

“You see one animal migrating, you don’t know if it’s migrating by itself, if it’s migrating with a calf, or if it’s migrating with 40 other animals,” Kauffman said.

Remote cameras — which can be left in the backcountry for days, weeks or even months — help fill in blanks by showing how many animals are on the move over a given period, he said.

Where to position them requires careful forethought. Clustering several around a watering hole, for instance, might produce many images but not a thorough profile of a population.

“There’s this tension between subjectivity in where you put your camera and where it’s statistically sound,” Harris said.

Sometimes smart-alecky humans turn up among the images. “I’ve seen people moon cameras, and that’s always funny,” he said.

Remote video can also reveal details about animal behavior, including the mewling sounds of migrating mule deer. And live-streaming cameras for everything from bison in Saskatchewan, Canada, to the underwater kelp forest off California’s Channel Islands are always popular.

As with all human intrusion into nature, remote cameras have downsides. Animals such as wolverines and bears have been known to attack them, though whether out of curiosity or aggression is hard to say.

Also, the devices have become popular tools to help hunters scout for game, prompting a debate over fair-chase ethics. Then there’s the whole subjective thing about going into nature to get away from it all, including surveillance cameras.

Anyway, to answer the question: A bighorn sheep that looks like it’s smiling probably isn’t saying “cheese” but sniffing pheromones and other scents in what’s called a flehmen response, said Harris.